General Analytical Solution for Two-group, Two-point Variance-to-mean Formulas and Their Application to Safeguards

The theory of Feynman-alpha method was extended to two-point one-group, two-group onepoint,
and two-point two-group versions by using the Kolmogorov forward master equation with
complete description of various types of reactions for neutrons. The motivation for this work
is related to the fact that the traditional one-group one-region Feynman-alpha formula was
elaborated and used for thermal systems in which the thermal
ux and the lifetime of thermal
neutrons dominates. However, this approach does not fully describe the effects of the re
ector
in the fast neutron systems, as well as heavily re
ected thermal systems.
Therefore, in the present work the two-group one-point, the two-point one-group and twogroup
two-point formulas were elaborated for different types of detections. Previously, the
two-group one-point formula described only detections of fast neutrons and at the same time
neglected the fast fissions, while the two-point one-group formula were limited to the case where
source term and detections were considered only for a core region. The quantitative assessment
of the formulas with regards to applications in safeguards and accelerator-driven system was
made through MCNPX and MCNP-PoliMi simulations. The results indicate a possibility to use
Feynman-alpha method to differentiate between various isotopic compositions of nuclear fuel.

BibTeX @mastersthesis{Ziguan2013,author={Ziguan, Wang},title={General Analytical Solution for Two-group, Two-point Variance-to-mean Formulas and Their Application to Safeguards},abstract={The theory of Feynman-alpha method was extended to two-point one-group, two-group onepoint,
and two-point two-group versions by using the Kolmogorov forward master equation with
complete description of various types of reactions for neutrons. The motivation for this work
is related to the fact that the traditional one-group one-region Feynman-alpha formula was
elaborated and used for thermal systems in which the thermal
ux and the lifetime of thermal
neutrons dominates. However, this approach does not fully describe the effects of the re
ector
in the fast neutron systems, as well as heavily re
ected thermal systems.
Therefore, in the present work the two-group one-point, the two-point one-group and twogroup
two-point formulas were elaborated for different types of detections. Previously, the
two-group one-point formula described only detections of fast neutrons and at the same time
neglected the fast fissions, while the two-point one-group formula were limited to the case where
source term and detections were considered only for a core region. The quantitative assessment
of the formulas with regards to applications in safeguards and accelerator-driven system was
made through MCNPX and MCNP-PoliMi simulations. The results indicate a possibility to use
Feynman-alpha method to differentiate between various isotopic compositions of nuclear fuel.},publisher={Institutionen för teknisk fysik, Nukleär teknik, Chalmers tekniska högskola},place={Göteborg},year={2013},series={CTH-NT - Chalmers University of Technology, Nuclear Engineering, no: },note={52},}

RefWorks RT GenericSR PrintID 186350A1 Ziguan, WangT1 General Analytical Solution for Two-group, Two-point Variance-to-mean Formulas and Their Application to SafeguardsYR 2013AB The theory of Feynman-alpha method was extended to two-point one-group, two-group onepoint,
and two-point two-group versions by using the Kolmogorov forward master equation with
complete description of various types of reactions for neutrons. The motivation for this work
is related to the fact that the traditional one-group one-region Feynman-alpha formula was
elaborated and used for thermal systems in which the thermal
ux and the lifetime of thermal
neutrons dominates. However, this approach does not fully describe the effects of the re
ector
in the fast neutron systems, as well as heavily re
ected thermal systems.
Therefore, in the present work the two-group one-point, the two-point one-group and twogroup
two-point formulas were elaborated for different types of detections. Previously, the
two-group one-point formula described only detections of fast neutrons and at the same time
neglected the fast fissions, while the two-point one-group formula were limited to the case where
source term and detections were considered only for a core region. The quantitative assessment
of the formulas with regards to applications in safeguards and accelerator-driven system was
made through MCNPX and MCNP-PoliMi simulations. The results indicate a possibility to use
Feynman-alpha method to differentiate between various isotopic compositions of nuclear fuel.PB Institutionen för teknisk fysik, Nukleär teknik, Chalmers tekniska högskola,T3 CTH-NT - Chalmers University of Technology, Nuclear Engineering, no: LA engOL 30